Driving and stopping mechanism.



3 SHEETS-SHEET 1.

'Patented oet. 23, 1,917.11

UNET@ @TT ATEN AUGUST n. sonoEi'vnv, or s'cMEavInLE, '-rvrAssnoHUsETT's, Assfr'eivon'ro RE'ECE sI-IOE'L MACHINERY comer-ina. @E EosT-oiv, MASSACHUSETTS, .a ooEPoEATIoN '0E MAINE.

DRIVING :AN'D STOPPING 'lIECH'A/NISIVI.

Speei'cationgof Letters Tatent.

Patented 0013.23, 1917.

Application-ledhugust 11, 1916. Serial No. 114,386.

tum is present due to the weight -or high speed of the rotating parts, and wherein the starting and stopping of the same are very frequent occurrences.

The main object of this invention is to provide for the stoppage of such a machine so as to insure a Viinal predetermined angular position of the driven shaft thereof, without shock, quickly, and in an easy and positive manner. lt is a further object of this invention to accomplish the abovein an automatic mannerwith the least .possible attention or skill on the part of the operator.

lt is a further object of this invention to provide means to disengage the high speed power from the shaft of a machine and to apply retarding action to the said shaft, and to position the low speed positive drive mechanism for instant action when called upon. This position of the parts will be maintained until just before the final angular position of the shaft has been reached,

when the retarding means will be released, and immediately thereafter the low speed positive drive will he Adisengaged. and the final stopping mechanism will be brought into play.

Further objects of the invention will be more fully pointed out in the description hereinafter given.

For the purpose of illustrating the vinvention, one preferred form thereof is illustrated in the drawings, this form having been found to give satisfactory and reliable results, although it is understood that the.

various instrumentalities of which ythe invention consists can ybe variously arranged and organized, and that the invention is not limited to the precise arrangement and organization of these instrumentalities as herein shown and described.

Figure Vl is a left elevation :partly in rsec- Fig. 2 is a front elevation of the mechanism shown in Fig. 1, with Ithe machine framegor case shown in section to better disclose the invention.

3 is a .part left elevation viewing F ig. 1 showing the Vbrake orshaft retarding mea-ns and some of its connections.

is a sectionV on the line ht Fig. l.

Fig. 5 is an enlarged detail in left elevation viewing Fig. i of some-of the partsof the slow speed positive'drive in'engaged position. i

Fig. :6 is a right elevation of certain par-ts of the mechanism, taken partly in section on 'the plane 6 -6 of Fig. 2. y

Figs. 7 ya-nd are similar views showing the parts in di''erent stages of operation.

Fig.. 9 is a detail section on the line 9-9 Fig. 1.

Fig. l0 is a detail section on the line lO--lO Fig. 2.

Fig. 1l is diagramo the `pedal control action.y

vSimilar charactersV designate like parts throughout the several figures of lthe drawing.

With the exception of Figs. -5-7 and 8 the vdrawings show the parts in theirposition after the machine `has been stopped. In this present inventionit will be understood that the initial action for stoppage is vcaused by the operator, and 4the subsequent actions are under the control of a driven shaft l'ofthe machine to which this inven-tionis to be applied.

A pedal Yor manually operated lever is moved by the operator when it is desired, to stop the machine, such movement disengarging the high speed power from the driven shaft and applying retarding means thereto, such for insta-nce. asa bandbra'ke.

At the same time, the low speed positive drive devices are .positioned for instant faction yand vwill engage 4for opera-tion when the speed 'of' the driven sha-ft has Ebeen retarded to that of the lowspeed drive devices.

Si-nce the time inv which the low speed drive .is in operation is extremely short and to eliminate momentum as much 'as possible, it isdeemed advisable tow-continue the retardi-ng Aaction untiljustbefore the 4lowv speed is disengaged, which immediately precedes the tinal positive stoppage of the shaft.

The release of the retarding means and the disengagement of the low speed drive as well as the final stoppage of the shaft are automatically obtained through the medium of a cam or control device mounted on the driven shaft.

Referring to the drawings.

The base 15 has upstanding therefrom the post or column 16 of suitable size and construction as to receive the head or operative parts of the machine to be mounted thereon but not shown herein.

Journaled in the bearings 17 and the post 16 is the main driven shaft 18 of a stitching or other machine which is to be driven and stopped frequently during the opera tion thereof. Loosely mounted on the shaft 18 is a pulley 19 to be hereinafter known as the high speed pulley, and the pulley 2O to be hereinafter known as the low speed pulley.

A counter'shaft 21 has fast thereon the pulleys 22-23 belted to the high and low speed pulleys 19-20 respectively.

Splined to the shaft 18 and slidable axially thereon is a clutch member 211 provided with a disk 25 adapted to engage the face of the high' speed pulley 19 see Fig. 1.

At its left end the clutch 24h has a disk 26 to which spring pressed pawls are pivotally mounted see Figs. 1, i and 5.

The low speed pulley is provided with ratchet teeth as at 28 adapted to be engaged by the pawls 27 at certain times.

The mechanism employed to slide the clutch 2li to its various positions consists of a bifurcated lever 29 pivoted at 30 to the base 15, and having its depending arm 31 pivotally attached to the link 32 which in turn is pivoted to the swinging arm 33 fulcrumed at 34 in the base 15. 'lie upper ends of the lever 29 are engaged with the studs of a loose ring surrounding the sleeve of the clutch 24.

The link 32 and the arm 33 form a toggle connection, the breaking joint of which has a link connection 35 with the left end of a lever or pedal 36 suitably fulcrumed at 37 to the base 15.

rlhe pedal 36 is at times under the control of a strong spring 38, see Fig. 1. lit is obvious that the movement of the pedal 36 downwardly will cause the clutch 24 to engage the high speed pulley 19. The reverse or complete upward movement thereof would cause the clutch to disengage from the highv speed pulley and slide the disk 26 and the pawls 27 into engaging position with the teeth of the low speed pulley 19 and at the same time apply the brake or shaft retarding device.

A third position of the pedal 36 and the one shown in the drawing places the clutch intenso 24E in such position that neither of the pulleys 19-2O are engaged and the machine is in stopped position.

ln this invention a retarding mechanism in connection with the shaft 18 is employed, r

that is put in operation directly after the disengagement of the high speed pulley 19 from the clutch 2&1, the same positioning the pawls 27 for operative engagement with the low speed pulley 19.

Fast on the shaft 18 at its left end see Figs. 1 and 3 is a brake drum 39 loosely surrounding which is a two part brake band et() pivoted at 111 to an upward extension of the bearing 17.

rllhe lower ends of the band 410 are connected by toggle links 12 which are in turn connected to a pin 413 slidably mounted in a boss 414.- of the base 15.

rlhe lower end of the pin 43 is threaded to receive the adjusting nuts 45 between ,vhicli, and loosely surrounding the pin 43, is the adjustable collar 46.

Fulcrumed to the base 15 at l? is a. swinging 18 connected to the arm 33 by the link 19 and +o the collar i6 by means of the link 50.

1t will be evident that the upward movement of the pedal 86 through the action of the spring 88 and the link and lever connections will cause the band t() to be tightened about the drum 39, and thereby quickly, and without shock, retard the rotation of the shaft 1S sufficiently to reduce its speed to that of the low speed pulley 2O so that the pawls 27 will engage the teeth 28 of the low epee pulley 9.0 and thereafter for a limited time the shaft 18 will be driven by such engagement.

rlhe stages of the stopping operation just described have been so far under the control of the operator through the pedal 36. The iinal operations of stopping which are automatic in their action will now be eX- plained.

liast to the shaft 18 at its right end see Figs. 1 and 2 is a bevel gear 51 meshing with a similar gear 52 fast on the cross shaft 53 which has suitable bearings in the base 15.

it its right end TFig. 2 the shaft 53 has fast to it a spiral gear 5e meshing with a similar gear 55 fast on the upright shaft 56 leading to the machine head not shown.

Slidable axially on the squared portion of the cross shaft 58 is a control or stop cam 57 adapted to be shifted into and out of operative position with a spring pressed cam follower 58 to be further described.

The cam 57 is provided with a grooved collar adapted to be engaged by roller studsv in. the ends of a forked bell crank lever 59 pivoted at 60 to a bracket 61 fast on the base 15, see Fig. 2.

The bell crank 59 and consequently the control cam 57 are shifted into the position .i

und

nee-agees The spindle 62 is provided with suitable adjusting'and stop `nuts to regulate the coinpression of the spring and the upward throw of the spindle respectively.

Viewing' Fig'. 10 it will be seen that vthe squared shank of the spindle 62 has teeth cut in one side thereof adapted at times to be engaged by the toothed end of ya spring,` pressed plunger 65 slidalole in an extension forming' part of the bearing 64.

The said plunger 65 has van outwardly.

extending portion 66 into which is threaded and clamped the adjustable screw 67 a guiding' slot 68 beingr provided in the extension for the said portion 66.

Pivoted to the lower end of the lever or arm 29 vis a link 69 its right end being in turn pivoted to a plunger 7 0 adapted to at times engage the screw 67 and move the toothed plunger 65 `out of engagement with the spindle 62 thereby .allowing said spindle to assume the lposition `shown in Fig. '2 by the expansion of its spring. The control cani 57, see Figs, Qf67 `and8, is of peculiarconstruction, it having a depression or 4cut away portion 7l, to allow it vto be shifted.

al stop shoulder or abutment 74.

lt will be noted that the lower Aend of the follower 58 is threaded to receive adjustable stop and contact nuts Z5-76 respectively', and passes loosely through a hole provided therefor in the pedal 3G the purpose of which will be hereinafter explained.

During the normal running of the machine the cam 59 will occupy a position on the shaft said follower will occupy its highest position shown in Fip'. 7. As previously eX- plained when the pedal 86 is depressed to its lowest position as indicated at 36a in the diagram Fig. 11 the clutch 2d will have engaged the high speed pulley 19 and fthe machine will loe kin operation.

lllhen, however. the operator desires to stop the machine the pedal 36 is allowed to rise under the action of the spring' 38 and in so doing' passes through the several posi- 18 to the left of its follower 58.

86" where the said pedal may fbe locked, lea ving' both ythe'highfand -low 'speed clutches as well as'the shaft retarding deviceout of oi'ieratiive position. f

1F urther-fmovement of the ingdeviceor brake-will be applied, at which time `the pawls "27 will have reached the ratchet engaging position but are 4*not engained' therewith. 36e indicates the position when the control cam or stop `is released.

l3nt this point-if the depression 71 lof the cam 57 is in registerwvith the follower 58 the said lcam will loe permitted to occupy its operative positionover the said follower.

If, however, the said depression and followerl 58 do not register, the cam 57 will be 4retarded 'in its 'sliding movement by means-of its :gua-rd position 7 2 meeting the side of the follower 58 and will so remain until said depression 7'1 and follower 58 do register.

At Sif the pedal 3G has reached Vitshighest swing' at which time the lowspeed. control and the 'retardiii'ig' device or brake are in full operation. v K- i Meanwhilefthecain 5'? has been positioned to slightlydepress the follower 58.

At the .position indicated at 36@ the arm 311 will have moved vthe Allink G9 and pin 70 to the "ight, see Figs.l 1r, 9 and' lO'to cause the said pin 70 'to .meet'lthe screw 67 and force the toothed plunger 65 out 'of ei1ga.. gel

ment lwith the spindle 62. The springsurrounding' the spindle 62 will now expand and through the bell crank 59 will force the cam 57 to the right viewing Fig. 2. As previously explained, the'cam will be held from its complete lateral movement by the `follower 58 if the cam depression 71 should not register therewith.

Aat 'this time Athe shaft 18 and the cani 57 are 'being' rotated but a ,eradually reducing; speed and such speed will continue to li.

its movement rtlie-reover and in its rotation its guard portieri 72- will ride over and slightly depress the plunger 58.

pedal upward into fthe position indicateda't 36d the retard- This relative position lof the cam vand folr` lower continues for approximately three` quarters of va revolution of the `cam 57, givinn' ample time for the retardin'g' of the shaft to the required speed, for the low speed drive to engage and positively rotate the shaft 18 a distance equal yto `that -required te bring; 'the shaft into Aor ai'iproximat-ely its linafli stoppiup,a positicm.V

The action of the i.earn 57 depressin .2` vthe plunger 58 has a 'slight retarding eect `en the shafts 5B-18 which is used to advantage at the time :of lfinal stoppage of said -fshafts shafts Vlhen the raised part of the cam 73 has reached the follower 58 and just before the shoulder 74 reaches the follower 58, the said follower is further depressed against the action of its spring and the Contact nuts at its lower end will engage the pedal 36. rlChe pedal 36 will now in turn be depressed and on its downward movement will first release the brake band l0 and immediately thereafter the pawls 27 will be withdrawn from the teeth 28.

Closely following the withdrawal of the pawls 27 the shoulder 74; will meet the follower S and a positive stoppage of the 1&3-53 willvoccur with the lever 36 in its mid or neutral position leaving the high and low .speed drives and the retarding device out of operation.

ft will be understood that the several connections controlling the stopping mechanism will be so arranged and adjusted that the below-enumerated performances thereof will first eliminate the high speed drive, apply the brake to eliminate destructive momentum and at the proper time cause the low speed drive to become effective. rfhe brake mechanism must of necessity begin its action and reduce the high speed of the driven shaft to that of the low speed drive before said low speed drive becomes operative even though the said low speed mechanism is in operative position.

So too the bralre mechanism may be released prior to the disengagement of the low speed drive to insure a positive movement of the shaft to approximately its final stopping position. he low speed drive in its turn must be disengaged just prior to the engagement of the cam shoulder 74 and fol lower 58. Such arrangement of the parts insures the operationthereof in a positive and easy manner, dependence upon the momentum of the machine not being necessary or even considered in the proper performance of the stopping devices.

From the foregoing it will be readily seen that it is an important feature of this invention that the speed of the driven shaft shall be reduced to the speed of the positive low speed drive before the low speed drive becomes effective.

ft is also a feature of this invention that he speed reducing medium shallV be operated independently of the low speed drive devices, as in the present instance by the action of a brake after the high speed has been thrown out.

lt is believed that the many advantages of this invention will be fully understood from the foregoing description.

rflhe invention hereinabove described may be said to be a stop motion for high speed power driven machines which comprises a braking means for reducing the speed of the nea-epee shaft of the machine before its stoppage, togetherl with a slow drive means for driving the shaft by power at a certain low or reduced speed toward or to the final predetermined stopping position. rlhe slow drive means is one which operates through a special kind of clutch such as a pawl and ratchet that is engageable to drive but not to retard the shaft. The pawl and ratchet clutch is incapable of retarding. As a result the slow drive means comes into effect at that time during the braking action when the shaft speed has been lowered to the reduced speed, that is, the speed of the slow drive means. rlhe slow drive means is thereafter disengaged at a suitable point to enable the shaft to be stopped in a predetermined position. A final stop device may be employed but impact is not always necessary and, indeed, the speed reducing brake may be left in effect throughout and after the slow drive so that on disengagement o f the latter the shaft is finally stopped in a definite position.

l claim:

l. fn a driving and stopping mechanism for power operated machines, the combination, of a high speed member; a low speed member; a driven shaft; a retarding device operable thereupon; a shiftable member adapted to be moved toward and from said high and low speed members; means carried by said shiftable member adapted to positively engage said low speed member; and control means for said shiftable member independent of said shaft, said means eecting the separation of the shiftable member and the high speed member, and applying the retarding device to said shaft prior to the positive engagement of said means carried by the shiftable member, and said low speed member.

fn a driving and stopping mechanism for power operated machines, the combination, of high and low speed drive means operable in the same direction; a driven shaft; retarding means operable upon said shaft and adapted to act independently of said low speed drive means; and means independent of said shaft to disengage the high speed and apply the retardingmeans, and to position the low speed drive means for operation prior to the actuation of the retarding means.

8. ln a driving and stopping mechanism for power operated machines, the combination, of high and low speed drive means; a driven shaft; retarding` means operable upon said shaft; means independent of said shaft to disengage the high speed and apply the retarding means and to position the low speed drive means for operation prior to the actuation of the retarding means; a final stop device; and automatic means to successively release the retarding means and disenga-ge the low speed drive prior to the final stoppage of the shaft.

d. In a driving and stopping mechanism for power operated machines, the combination, of high and low speed drive means adapted to operate inthe same direction; a driven shaft; a-stop for said shaft; retarding means operable independently of said low speed drive means upon. said shaft; single means under the direct control of the operator to successively disengage the high speed, apply the shaft retarding means, and position the low speed drive means for operation prior to the actuation of the said retarding means; and automatic means to successively release the retarding means, disengage the low speed drive means, adjust the operators control means to neutral position, and cause a i'inal stoppage-of the driven shaft.

5. In a driving and stepping mechanism for power driven machines, the combination of a high speed member; a low speed member; a driven shaft; la high speed friction clutch and a low speed positive clutch revolubly mounted upon said shaft; a brake mechanism adapted to operate directly on said shaft; and means to move said clutches into and out of operative-position with the said speed members whereby the'shaft will be i'irst retarded and thereafter will be positively driven at a reduced speed in the same direction.

6. In a driving andv stopping mechanism for power driven machines, the combination, of afhigh speed friction clutch; a low 'speed positive clutch normally retained in disengaged position; a driven shaft; a brake thereon; means externally of the shaft- Yto disengage the friction clutch and posit-ion the positive clutch for operation prior'to the braking of the shaft; and means to canse the operation of the low speed clutch positive at a predetermined speed of the driven shaft. 7. In a driving and stopping mechanism for power driven machines the combination, of a high speed driveV means, a low speed drive means; a driven shaft; retarding means operable independently of said low speed drive means upon said shaft; means to'disengage the high speed drive means and apply the retardingmeans; and means to thereafter engage tlie low-speed drive'meafns to drive the said shaft in the'same direction yat a predetermind speed of saidfshaft.

S. In a driving and stopping mechanism for power driven'machines'the combination,

ofa high speed drive means; a lowl speed f .6.5 releasethe brakeydisengage the: low speed drive, adjust the said: control to neutral position ,and positively stop the said shaft at a predetermined angular position.

9. In a driving and stopping mechanism for power driven machines the combination, of a: high speed drive means;A a low speed drive means; a driven shaft; means operable independently of said low speed drive means upon said shaft; means vto disengage the high speed drive means; posidriven shaft; a brake thereon operably independent of4 said low speed drive; means common to said` high speed drive and said Vbrake adapted to disengage said high speed drive and set said brake; and low speed drive means adapted to operate to drive the.

shaft inthe same direction after the said brake has been set. f

11. In a driving and stopping mechanism forl power drivenl machines, the combination,

of a high speed drive; a low speed drive means; a driven shaft; a brake thereon; means to-shift from high tolow speed, said means first positioning the low speed vdrive and then setting the brake; means to operate ythe-low speed drive aftervsaid brake is set, and means to thereafter disconnect said low speed drive prior tothe iinal stoppage of said shaft. f

12. In a driving'and stoppingl mechanism for power driven machines,.the-combination, of a high speed drive; a continuously rotating low-speed .positive drive; a driven shaft; retarding means operable thereon independently of said low speed drive; means tolshift from high to lowk speed drive position the low speed drive andl operate the retarding means; means topositively engage the low .speed drive at a predetermined speed of the shaft; 'and means to disengage the low speed positive drive and thereafter stop said shaft at a predetermined angular position..

f '718. In adiiving and stopping mechanism for power `driven machines, the combination, of. avliigh speed drive";'a low speed drive; a drivenshaft; aspeed control; a brake operable independently of the low speed drive adapted'to reduce the speed of the shaft to apredetermined amount after. thehigh speed has been thrown out; means subject to the reducedspeed ofthe driven shaft tooperate;

the low speed drive at a uniform predetermined'speed; means 'tov disengagfe said low speed drive;1and means .to positively stopthe shaft at ai predetermined angular position. Y

' 14. In af-driv-ing and stoppingmechanism..

retarding lll@ for power operated machines, the combination, of an operating shaft; continuously rotating high and low speed driving mechaisins therefor; a retarding device operable upon said shaft independently of said driving mechanisms; means to disconnect the high speed mechanism from the shaft and subsequently apply the retardiiig mechanism thereto; means to positively engage the low speed mechanism to the shaft when sufficiently retarded; means to disengage the low speed drive means; and means to thereafter positively stop the shaft at a predetermined angular position.

l5. fn a driving and stopping mechanism for power operated machines, the combination, of. an operating shaft; high and low speed drive means therefor; a brake operable independently of said drive means upon said shaft; manually operated means to disconnect the high speed drive from said shaft and subsequently apply the brake thereto; means to positively engage the low speed drive means to said shaft at a predetermined speed of said shaft after the brake has been applied; and automatic means to disengage said low speed drive and stop the said shaft at a predetermined aiigular'position.

i6. A stop motion for high speed power driven machines, comprising` in combination, braking means for reducing the speed of the machine shaft before its stoppage, slow drive means for power driving the shaft at a reduced speed toward a predetermined stopping position, said slow drive means operating through a one way driving clutch, which is engageable to drive but not to retard the shaft, whereby during the braking action the slow drive means comes into effect when the shaft speed is lowered to the reduced speed, and means for disengaging the slow drive means at a suitable point to enable the shaft to be stopped in a predetermined position.

17. 'ifi stop-motion for high1speed power driven machines comprisino1 in combination, a retarding means which is normally inoper- 1 ative but adapted to be rendered operative,

means constructed to act on the shaft through a connection which is engageable to drive but not to retard the shaft, whereby the slow driving means comes into effect automatically when the shaft speed has been retarded to that of the slow driving means; and means for disengaging the slow driving means before the iinal stoppage.

i8. A stop-motion for high speed power driven machines comprising in combination, a retarding means which is normally inoperative but adapted to be lrendered operative,

when the machine is to be stopped, for quickly reducing the speed of the machine shaft; a slow driving means for power-driving the shaft at a speed materially less than the full speed thereof; means for causing the operative engagement of the slow driving means during the rotation of the retarded shaft whereby the latter is continued in rotation toward the final stoppin@ point, and for subsequently disengaging the slow driving means.

19. A. stop-motion for high speed power driven machines comprising in combination, a retarding means which is normally inoperative but adapted to be rendered operative, wnen the machine is to be stopped, for quickly reducing the speed of the machine shaft; a slow driving means for power-driving the shaft at a speed materially less than the full speed thereof, said slow driving means constructed to exert on the shaft only a forward driving force, wherebyl the slow driving means comes into effect automatically when the shaft speed has been retarded to that of theslow driving means; and means for disengaging the slow driving means before the final stoppage.

20. A stop-motion for high speed power driven machines comprising in combination, a retarding means which is normally inoperative but adapted to be rendered operative, when the machine is to be stopped, for quickly reducing the speed of the machine shaft; a slow driving means for powerdriving the shaft at a speed materially less than the full speed thereof, said slow driving means constructed to exert on the shaft only a forward driving force, whereby the slow driving means comes into effect automatically when the shaft speed has been req tarded to that of the slow driving means, said slow driving means being adjustable into and out of operative condition; and means for adjusting the same into operative condition before the shaft is retarded to the lower speed and for subsequently adjusting the same out of operative condition before the final stoppage.

21. A stop-motion for high' speed power driven machines comprising in combination, Va retarding means which is normally inoperative but adapted to be rendered operative, when the machine is to be stopped, for quickly reducing the speed of the machine shaft; a slow driving means for powerdrving the shaft at a speed materially less than the full speed thereof, said slow driving means constructed to act on the shaft through a connection which is engageable to drive but not to retard the shaft, whereby the slow driving means comes into edect automatically when the shaft speed has been retarded to that of the slow driving means; means for subsequently disenga ging the slow driving means at a predetermined point in the shafts rotation; and means for stopping the shaft in a predetermined final position.

22. A stop-motion for high speed power driven machines comprising in combination, a slow driving means for powendriving the retarded shaft at a speed materially less than the full speed thereof, said slow driving means constructed to act on the shaft through a connection which is engageable to drive but not to retard the shaft, whereby the slow driving means comes into effect automatically when the shaft speed hasl slowed down to that of the slow driving means; means for subsequently disengaging the slow driving means at a predetermined point in the sha ts rotation; and means for further retarding, and finally stopping, the shaft in a predetermined final position.

23. A driving and stopping mechanism for power driven machines, in combination, a high speed drive; a low speed drive; a driven shaft; a brake on said shaft; means to shift from high to low speed, said means including devices to position the low speed drive for operation;'means associated with the low speed drive adapted to prevent the premature actuation of said low speed drive means; means to disengage said low speed drive; and means to stop the shaft at a predetermined angular position.

?AA driving and stopping mechanism for power driven machines, in combination, a high speed drive; a low speed positive drive; a driven shaft; a brake on said shaft; means to shift from high to low speed; means to position said low speed drive means prior to the actuation of said brake; and

means associated with the low speed drive means adapted to prevent a premature en gagement thereof; means to disengage said low speed drive; and means tothereafter stop the shaft at a predetermined angular position. Y

25. A driving and stopping mechanism for power driven machines, in combination, a high speed drive; a low speed positive drive; a driven shaft; a brake on said shaft; means associated with said low speed drive means adapted to prevent a premature driving engagement of said low speed drive means; means to disengage said lowv speed drive means; and means to stop the shaft at a predetermined angular position.

26. A driving and stopping mechanism for power driven machines, in combination, a constantly driven high speed member; a constantly driven low' speed member; a

driven shaft; a high speed clutch, and avlowv AUGUST R. SCHOENKY.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents Washington, D. G. 

